Po-02-026 long-term mortality in patients with ischemic versus nonischemic cardiomyopathy following cardiac resynchronization therapy

Studies have shown comparable benefits in all-cause mortality in patients with ischemic (ICM) vs. nonischemic cardiomyopathy (NICM) following cardiac resynchronization therapy (CRT). Data on long-term outcomes of CRT between these etiologies is limited. We aim to evaluate long-term all-cause mortality in patients with ICM and NICM that have undergone CRT. We conducted a retrospective analysis of patients with ICM and NICM that have undergone CRT within the Mayo Clinic Health System since 2002. Patients with LVEF ≤ 35% pre-implant were included in the study. All-cause mortality data were compared between the two groups. Data from 872 (59%) patients with ICM and 614 (41%) patients with NICM that underwent CRT implantation between 11/2002 and 7/2022 were analyzed. 85% of patients with ICM were males compared to 64% of patients with NICM (p<0.001). The average age at implant was significantly lower among patients with NICM compared to ICM (68 vs. 73 years, p<0.001). The median age at implant among patients with NICM was 69 (IQR 59-77.5), and among patients with ICM was 74 (interquartile range [IQR] 68-79). Mean pre-implant LVEFs were 22% in both groups (p = NS). Survival distributions for patients with ICM and NICM that had undergone CRT were significantly different (log-rank p<0.001), with lower all-cause mortality for patients with NICM than with ICM. Following CRT, patients with NICM have lower all-cause mortality as compared to patients with ICM. However, randomized trials with control group data are needed to comment on the relative mortality benefit of CRT in these two modalities over the long term.